close up (diotpter) lenses

[alanrockwood]

I am interested in learning more about the technical quality of photos made with close up lenses. To get one issue out of the way, I do understand that achromatic doublets provide the best optical quality, so let's focus on simple single element diopter lenses.

It is often stated that quality suffers when using simple closeup lenses. Sometimes the additional comment is appended: "unless stopped down". However, I am having a hard time finding any test results to confirm these comments.

Also, the comments about stopping the lens down when using closeup filters seems superfluous to me, since one almost always stops down when doing close ups anyway in order to gain depth of field.

Any comments?

 

[ic-racer]

The lenses are pretty inexpensive; I think most people that have used them can observe if the results are acceptable with one roll of film.

 

[Dan Fromm]

Alan, when I started out several centuries ago I had a Nikkormat FTN, a 50/1.4 Nikkor, and a couple of Nikon's own single element "closeup lenses." They might have worked well with other lenses, but on the one lens I had they were disasters. Bad field curvature even stopped well down and not very sharp. I've never known whether to blame the lens or the diopters, but the combination was unusable. As soon as I could scrape the money together I bought a 55/3.5 MicroNikkor. That was a great lens.

If I were you I'd ante up and buy a MicroNikkor. They're not that expensive used and getting one will save you the costs of a mistake like mine.

 

[MattKing]

The one advantage of close up (diopter) lenses is that they permit higher magnifications without requiring you to work at closer distances. In some cases, that makes it easier to light your subject.

 

[Stephen Schoof]

I used the single-element (usually Hoya +1 or +2) for years and was mostly satisfied as long as I stayed within their limitations. I shoot slow-speed slide film and am fairly picky about sharpness, but I got good results when I used them with short to moderate telephotos stopped down. Now I use primarily the Nikon double-element 5T and 6T and they are less limiting and offer better quality. I'm sure a real macro lens is the best way to go if you're doing a lot of close-up work, but for me the diopters are a weight-saver on backpacking trips when I want to turn a lightweight 100mm series E or 70-300mm f4/5.6 into a makeshift macro.

 

[elekm]

I've used these and haven't had any issues. However, the ones that I've used aren't the "one size fits all."

I use the lenses that are made for a specific camera and lens. For some cameras (cameras with fixed lenses), they are your only option if you want to shoot closeups.

 

[Dan Fromm]

Um, now that I think of it the OP's question is a very old one. Several centuries ago Modern Photography ran educational articles on a two year cycle. So every two years they addressed the question "which is better, a closeup lens or an extension tube?" This in the days when closeup lenses are all single element. The article addressed lenses for SLRs, not lenses for fixed lens range- or viewfinder cameras, which are poorly suited to closeup work.

The answer? It depends on the lens. Some give better image quality with added extension than with their focal lengths reduced, others give better image quality with their focal lengths reduced than with added extension.

Alan, I recommended that you get a MicroNikkor. Good advice, but only if you have a Nikon. Get a macro lens to fit your camera.

 

[frank]

Diopter lenses are a good solution for close up photography in terms of cost and ease of use, UNLESS you are wanting to shoot flat objects like coins and stamps were edge to edge and corner to corner sharpness is vital. A dedicated macro lens is best for this.

Diopter lenses introduce a pronounced curvature of focus, which likely won't be an issue when photographing 3-D objects like flowers and insects.

Extension tubes lie somewhere between, and quality depends highly on the particular lens you are using.

 

[Gerald C Koch]

Anything introduced into the optical path will degrade the image. You get what you pay for. Cheap lenses cause more loss that more expensive ones.

 

[JimCee]

I have a Nikon 6T Close-Up lens that I originally purchased for use with my Micro-Nikkor 70-180mm lens (it permits a 1:1 reproduction with that lens). Recently, I used the 6T with my Tamron SP 70-300mm VC f/4 lens on my Nikon D7000 camera. I was pleased with the result. A photo taken with that combination is shown.

Jim

 

[alanrockwood]

I wonder what aberrations dominate the image when using close up lenses.

Here is the context of this question. There is a result from optical theory that a simple meniscus lens can have zero spherical aberration under certain conditions.

Without going into all of the details, this occurs when there is a certain relationship between the refractive index of the lens and the radii of curvature of the two surfaces. The image distance and object distance also has to fulfill a certain relationship, specifically that the object and image are on the same side of the lens, and that the ratio of the distances equals the refractive index of the lens.

It turns out this this occurs when the object distance is less than the focal length of the lens, and the lens is is convex away from the object. Interestingly, this orientation of the convex surfaces is the opposite from the way closeup lenses are usually used. The lens surface is usually oriented as convex toward the object rather than away from the object. This is a prescription for increased spherical aberration. I wonder if better image quality could be obtained if the orientation of the diopter lens were reversed. This could be done using a threaded adapter to mount the diopter in front of the main lens.

 

[John Koehrer]

It sounds like you're gong to get yourself another project here. Are you ready?

To quote: "object and image are on the same side of the lens" and" "object distance is less than the focal length of the lens".

Since I'm an ignorant savage here, they both first sound like the object would be inside of any common sort of lens.

 

[thuggins]

Having experimented with both (single element) close-up lenses and extension tubes in the past, the close-up lenses are more convenient and easier to use, and I never had an issue with the image quality. Since I've now added a full set of Oly macro's to my collection it is not longer an issue. But macros are expensive and close-up lenses are cheap and readily available.

 

[alanrockwood]

To quote: "object and image are on the same side of the lens" and" "object distance is less than the focal length of the lens".

Since I'm an ignorant savage here, they both first sound like the object would be inside of any common sort of lens.

Here is the geometry for zero or minimal spherical aberration.

* * )
image object meniscus
position position lens

The main lens would be on the right, but is not convenient to draw using my primitive keyboard graphics.

Here is the geometry conventionally used.

* * (
image object meniscus
position position lens

The difference is the orientation of the curve of the meniscus lens.

By the way, the image in these figures is a virtual image and refers only to the image formed by the meniscus lens, not the full system. The image of the full system, which includes the main camera lens, is on the film plane.

Also, the apug system has stripped out spaces, so my figures are even worse in the posted version than in the version I originally created. For example, the labels in the posted image do not line up with the elements of the figure, but hopefully it is at least good enough to convey the concept.

 

[narsuitus]

I use close-up (diopter) lenses and I also use macro lenses. Both are useful to me.

I usually shoot with a macro lenses when I need to capture high-quality images.

When I need to travel with a light photographic load, I may carry a small fixed-lens camera and a few close-up (diopter) lenses just in case I need them.

Also, to prevent too much loss of image quality, I never shoot with stacked close-up lenses.

https://flic.kr/p/dUqdFY

 

[dynachrome]

I have a number of macro lenses but I still use close-up lenses when I need to. Sometimes a subject is at a distance or behind glass. Using a longer lens may make it difficult to get enough extension. In these cases, close-up lenses can be helpful. I have a small collection of mostly multi-element examples from Konica, Minolta, Nikon, Asahi, Topcon, Sigma, Canon, Toshiba and I'm sure others. Sigma supplied its Achromatic close-up lenses with certain zooms which did not focus very close on their own. In some situations it can be easier to focus a faster lens with a close-up lens attached than to focus a slower macro lens. This would happen in low light. You would still need to close down several stops when shooting with the close-up lens unless you were aiming for a soft or artistic result but without the ability to see the subject clearly, focusing can be difficult.

 

[AgX]

Another point only marginally addressed so far is that there basically are two types of close-up lenses: 1-element and 2-element-cemented ones. The cemented ones are more rare. And even Heliopan do not list them but only sell them on request.

 

[David Allen]

Having experimented with both (single element) close-up lenses and extension tubes in the past, the close-up lenses are more convenient and easier to use, and I never had an issue with the image quality. Since I've now added a full set of Oly macro's to my collection it is not longer an issue. But macros are expensive and close-up lenses are cheap and readily available.

I certainly agree that close-up lenses are both more convenient and easier to use than extension tubes. When I worked commercially, I used Hasselblad equipment with a range of lenses and backs. Close-ups (other than tight head shots) were not something that I had to tackle very often. The first time such an assignment arose, I bought Hasselblad extension tubes and a geared focussing rack that sat between the camera and the tripod. Whilst this worked, and the related maths is not complicated, I did not find it very convenient to use. I then experimented with some hired Hasselblad close-up lenses and found that they suited my way of working so I sold the extension tubes and bought a full set of close-up lenses. These worked for my occasional uses very well provide that you took great care to shield any stray light hitting the front of the close-up lens. For anything approaching more demanding use, rather than buy a dedicated macro lens, I would use my old MPP 5" x 4" as this offered a larger negative and movements.

Bests,

David.
www.dsallen.de

 

[alanrockwood]

By the way, I mentioned that it is possible to design a simple meniscus lens with no spherical aberration when operated under certain conditions. It is also possible to design the system to be free of both spherical aberration and coma, the so-called aplanatic condition. Astigmatism and other aberrations remain.

However, spherical aberration and coma are the two aberrations that, aside from chromatic aberrations, is most easily reduced by stopping the lens down, which is quite convenient if you are going to stop-down anyway to improve depth of field.

I have an old hard copy of the Melles Griot optics guide (Optics Guide 5) that has a good discussion of aplanatic design of meniscus lenses, though not in the exact context we are discussing here. I don't think the current online documentation from Melles Griot has that information.